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A method is proposed for investigating muon transfer from excited muonic hydrogen atoms to an element Z{gt}2, and is applied to argon measurements. It makes use of a comparison between the muonic x-ray intensity patterns of the Lyman series of this element measured in mixtures with and without hydrogen. The analysis of the data taken in two gas mixtures H{sub 2} + Ar at 15 bar with argon concentrations of 2{percent} (0.3{percent}), yields consistent results. In both mixtures, two thirds of the prompt argon x rays proceed from transfer from excited {mu}p{sup {asterisk}} states. The Coulomb capture ratio determined in both mixtures yields a mean value of A(H{sub 2},Ar) = 0.21(2), and agrees with the corresponding pionic ratio. {copyright} {ital 1997} {ital The American Physical Society}

The yields of muonic x rays of the Lyman series of nitrogen, neon and argon have been analysed to determine capture ratios A(Z1,Z2) in about thirty gaseous mixtures under different experimental conditions. In addition, capture ratios A(Z,H) have been determined in hydrogen mixtures by taking into account transfer processes from muonic hydrogen to elements Z. The influence of the spectral flux density of the muons on capture ratios has been analysed. Our per-atom ratios form a coherent set and confirm the value A(Ar,Ne) = 1. 262(10).

In this paper I discuss a neglected form of argument against religious belief-generically, 'the probabilistic argument from pluralism'. If the denial of a belief is equivalent to the disjunction of its alternatives, and if we may gain some idea as to the probabilities of such disjunctions by adding the separate probabilities of their mutually exclusive disjuncts, and if, moreover, the denials of many religious beliefs are disjunctions known to have two or more mutually exclusive members each possessing a significant degree or probability, then at any rate in many such cases, the denial of a religious belief can be shown to be more probable than it is - which is to say that the belief can be shown to be improbable. I consider a large number of responses to arguments of this form, concluding that none suffices to overthrow it altogether. Indeed, the argument remains as a significant threat to any religious belief confronted by a plurality of alternatives.

Recent experimental results on the muon exchange from muonic hydrogen to argon show that the reaction rate is energy dependent near 0.1 eV. A muonic hydrogen atom, formed by muon capture in H{sub 2} gas at 15 bars, is thermalized in a few hundreds of nanoseconds. If the muon transfer reaction occurs before that time, the rate is shown to be slightly lower compared to thermalized muonic atoms [{lambda}{sub pAr}=(1.63{plus_minus}0.09){times}10{sup 11} s{sup {minus}1}]. As an indirect consequence, the muon transfer rate from {mu}p to helium, determined by our group [R. Jacot-Guillarmod and co-workers, Phys. Rev. A {bold 38}, 6151 (1988)] is lowered by about 40{percent}. The present value {lambda}{sub pHe}=(0.51{plus_minus}0.19){times}10{sup 8} s{sup {minus}1} is in good agreement with other experiments. The transfer rate from muonic deuterium to argon shows also an energy dependence. The muon transfer rate to argon from the deuteron is {lambda}{sub dAr}=(0.86{plus_minus}0.04){times}10{sup 11} s{sup {minus}1} at room temperature. The intensity patterns of the muonic Lyman series of argon obtained by muon transfer from both hydrogen isotopes are determined and compared with theoretical predictions. {copyright} {ital 1997} {ital The American Physical Society}

Several experiments performed by our group in recent years have put into evidence the complex structure of the time distributions of the muonic X-rays following transfer from muonic hydrogen isotopes to heavier elements. Simulations have shown that a substantial fraction of the µp atoms in the ground state have epithermal energies. Therefore, an energy dependence of the transfer rate seems a reasonable assumption for the explanation of the complex time structure.

Muon transfer from hydrogen isotopes to helium is of importance in muon-catalyzed fusion and serves as a unique tool for the direct observation of the mesomolecular ion (pµHe)*. During two data-taking runs in 1994 and 1995 at PSI, measurements of the transfer from protium to helium were carried out using CCD's and Ge-diodes as independent X-ray detectors to obtain information on the time distribution and intensity of the 7 keV decay X-ray of the mesomolecular ion. Dual1H2 +4 He and triple1H2 + Ne +3,4He gas mixtures at low temperatures were investigated to extract transfer rates. Protium of high purity was available. For the first time a transfer rate from muonic protium to3He was measured. A general survey of our measurements and preliminary analysis is presented.

To investigate the energy dependence of muon transfer to oxygen, we performed measurements in gaseous mixtures of hydrogen and oxygen. The time distributions of the muonic oxygen X-rays showed the same structure as the one observed earlier in H2+SO2 mixtures. In the delayed part of these distributions, one can distinguish a short-time and a long-time component. From the latter, we deduced the transfer rates from thermalized muonic protium, respectively deuterium, to oxygen. The short-time component can be interpreted as being due to muon transfer from epithermal muonic hydrogen atoms. The time parameters are characteristic for the deceleration process as well as for energy-dependent transfer rates. With results of recent research on the formation and the thermalization of muonic hydrogen, we performed Monte Carlo simulations in order to test the hypothesis of an energy-dependent transfer rate.

I cannot resist remarking at the outset upon Howard-Snyder's label for the argument. If the latter were from Divine hiddenness, it could hardly be for atheism. The claim that God is hidden entails that God exists! But let that pass. I am more interested in commenting on (i) the way HowardSnyder sets up the discussion, his characterization of the argument and of the conditions necessary for its success; and on (ii) his (relevant) proposed defeaters. Let's begin with (i). While he relies on my work2 in clarifying the argument and in showing how certain of its premises might be defended, Howard-Snyder (presumably acting on the Principle of Charity) adds a clause to one of the premises I employ, and also inserts into the argument a premise I do not employ. Now this sort of move is in itself

William Alston's Perceiving God: The Epistemology of Religious Experience (Ithaca, NY: Cornell University Press, 1991) is a most significant contribution to the philosophy of religion. The product of 50 years' reflection on its topic (xi), this work provides a very thorough explication and defence of what Alston calls the ‘mystical perceptual practice’ (MP) – the practice of forming beliefs about the Ultimate on the basis of putative ‘direct experiential awareness’ thereof (pp. 103, 258). Alston argues, in particular, for the (epistemic) rationality of engaging in the Christian form of MP (CMP). On his view, those who participate in CMP are (in the absence of specific overriding considerations from within CMP) justified in forming beliefs as they do because their practice is ‘socially established’, has a ‘functioning overrider system’ and a ‘significant degree of self-support’; and because of the ‘lack of sufficient reasons to take the practice as unreliable’ (p. 224).

L'A. aborde le probleme du mal d'une maniere logique pour arriver a une conclusion contraire a celle qui est traditionnellement assumee par la philosophie de la religion. Il y a selon lui, une forme hybride de l'argument du mal qui trouve son origine dans des considerations de probabilite, mais qui d'autre part, procede de maniere deductive

The experimental muon transfer rates from muonic protium and deuterium to heavier elements show a complexZ dependence. Instead of the expected monotonicZ dependence considerable variations between neighboring elements are observed. Transfer to neon has a specially small rate. Furthermore, the time distribution of the muonic X-rays shows in a number of molecules a complex structure, and depends in the case of a H2 + CH4 gas mixture also on the total pressure.

A set of experiments is reviewed which makes use of the emission of muonic deuterium from the surface of a layer of solid hydrogen. The behaviour of muons in a solid target system has been studied via detection of muon decay electrons, muonic X-rays, and fusion products (neutrons and charged particles). The emission of muonic deuterium is understood to result from the Ramsauer-Townsend scattering minimum. The energy distribution of the emitted atoms ranges from tenths of eV to about 10 eV, and can be controlled to some extent. A proposal is described to use muonic tritium emission to measure the energy dependence of muonic molecular formation.

The ratios of prompt to delayed fission yields for the isotopes U-233, U-234, U-235, U-236, U-238, Np-237, Pu-242, and Pu-244 and the fission probabilities relative to each other have been investigated experimentally. Using the value of the total fission probability for Np-237 the absolute probabilities for prompt and delayed fission have been determined. The fission probabilities per muon capture P(fc) have been derived for all the isotopes and compared with an evaluation based on excitation functions from theory.

After the feasibility of vacuum isolated μ−d production was demonstrated at TRIUMF in 1989, development was begun on a target system that would take advantage of the process to aid in the understanding of the muon catalyzed fusion cycle. Minimal neutron backgrounds, the ability to use silicon detectors, and compatibility with tritium were considered important for a very versatile target system. The advantages which the target gives in isolating μCF process will be outlined.

A study of muonic238U has been performed in a combined (μ−,γ f) and (μ−,γγ) coincidence experiment to investigate the role of non-radiative transitions and their fission probabilities. An augmentation of the outer fission barrier ofΔEb=(0.6±0.1) MeV due to the presence of the muon is deduced. A significant contribution to the prompt fission yield not only results from the (2p→1s) and (3d→1s) non-radiative transitions, but also from other radiationless transitions. Specifically, the measured fission probabilities of the transitions (2p→1s), (3d→1s), and (3p→1s) are (1.5±0.4)%, (5.7±1.7)%, and (5.3±1.9)%, respectively.

The present work extends the systematics of nuclear charge radii obtained by the method of muonic atoms to nuclei with 8\ensuremath{\le}Z,N\ensuremath{\le}20. The accuracy of the measured muonic Lyman transition energies of generally \ensuremath{\le}10 eV leads to a precision in the model-independent nuclear charge radii differences of 2--3 am for the isotope shifts and 4--9 am for isotone shifts. Both isotope and isotone shifts within the s-d shell behave ``anomalously'' with respect to the systematics of heavier nuclei. However, such behavior is predicted on theoretical grounds, if mixing in the s-d shells and the strong deformation of some of the nuclei in this region are considered. We compare charge radii from elastic electron scattering data with muonic atom rms radii and suggest that observed deviations are possibly due to incomplete dispersion corrections.

Fission fragments from the reaction237Np(μ−,γ,f) have been measured in coincidence with muonic X-rays. The efficiency of the fission fragment detector is determined from (μ−,γ,f)-data of the same experiment. The total fission probability perμ-stopPt has been measured as well as the fission probabilities Pf of the non-radiative muonic (3d→1s)- and (2p→1s)-transitions; the latter has been divided into two parts leading to different mean excitation energiesE:P t =(54±17)%,P f (3d→1s)=(41±21)%,P f (2p→1s,E=6.218 MeV)=(61±19)%, andP f (2p→1s,E=6.525 MeV)=(57±18)%. The influence of the muon on the fission barrier is discussed. The fission probability after muon capture is compared with a calculated value using a distribution of nuclear excitation energies following muon capture and the fission probability as measured in a238U(3He,αf)-reaction.

The probabilities for non-radiative (n.r.) excitationsP n.r. in the muonic nuclides208Pb,232Th, and238U have been determined from (μ−,γγ)-measurements by comparing the intensities of muonic X-ray transitions in single and coincidence spectra. The value ofP n.r. (3p→1s), measured for the first time, is about 90% for the actinides232Th and238U, but only about 8% for208Pb. The value ofP n.r. (3d→1s) is found to be 10 % for233Th, 13% for238U, and about 4% for208Pb. For208Pb a vanishing strength of the n.r. decay of the 2p-level is found, while for232Th and for238U n.r. strengths of about 20% and 26%, respectively, are observed. By regarding two subcomplexes of the 2p→1s transitions leading to different mean excitation energies the n.r. transition probabilities were found to be different for238U only, 21.6% and 31.1.%, respectively.

The time spectra for muon induced fission of233U,234U,235U,236U,238U, and237Np were measured simultaneously, detecting both fragments in coincidence in a fast multi parallel plate avalanche detector. The observed mean lifetimes τ are 68.9 ± 0.3 ns, 70.6 ± 0.2 ns, 72.2 ±0.2 ns, 74.3 ± 0.3 ns, 77.0 ±0.4 ns, and 69.8 ±0.2 ns for the above isotopes, respectively. No second time component, tentatively ascribed to a possible fission isomer, was observed. The deduced total capture rates are compared with theoretical predictions.

To assess the validity and reliability of an office-based surrogate measure of lumbar spine-stabilization endurance capability; to establish norms and reliability in an asymptomatic group; and to compare their measures with those from a group of chronic mechanical low-back pain patients.: Eight healthy subjects participated in the tool-validation portion of the study that consisted of surface electromyographic (EMG) measurements of core muscle activation during prone and supine bridging. Subsequently, normative and test-retest reliability measures of prone and supine bridging duration were recorded from 43 subjects without back pain and were compared with those of 32 subjects with chronic mechanical low-back pain.: Surface EMG indicated significantly preferential activation of anterior core muscles during prone bridging and posterior core muscles during supine bridging. Mean bridge durations for subjects without back pain were 72.5 +/- 32.6 (mean +/- SD) secs in prone and 170.4 +/- 42.5 secs in supine. They were significantly less in subjects with back pain: 28.3 +/- 26.8 secs in prone and 76.7 +/- 48.9 secs in supine. Test-retest reliability using Pearson's correlation for prone and supine bridging was 0.78 and 0.84, respectively.: Bridging maneuvers seem to be practical, reliable, and valid methods of reflecting lumbar spine-stabilization endurance capability. Prone bridging preferentially challenges core flexors, whereas supine bridging recruits primarily the core extensors; both are compromised in patients with low-back pain.

Background: The Five Hills Health Region of Saskatchewan reported the highest West Nile virus (WNV) case rates in the 2003 outbreak. A serologic and telephone survey was undertaken to assess the seroprevalence of the virus and the knowledge, attitudes and behaviours of the residents. Methods: Respondents had to be at least 18 years of age, and residents of the Five Hills Health Region between July 1 st and September 15 th , 2003. Blood samples of respondents were tested at the National Microbiology Laboratory for flavivirus immunoglobulin using a WNV IgG ELISA and plaque reduction neutralization test. Descriptive analyses performed related to respondents’ demographics, knowledge, attitudes, behaviours, and seropositivity. WNV infection risk was assessed using odds ratio. Results: There were 619 questionnaire respondents, of whom 501 donated a blood sample. The seroprevalence of WNV in the Five Hills Health Region was 9.98% (95% CI 7.37-12.59%). Seropositivity of rural areas was 16.8% and urban was 3.2%. Most (97%) of participants thought WNV was an important health issue. Forty-eight percent of the participants used insect repellents containing DEET most of the time. There was good knowledge regarding WNV transmission and prevention of the spread of WNV. Rural compared to urban residents were six times more likely to be positive for WNV (OR=6.13, 95% CI 2.82-13.34). Interpretation: This is the highest seroprevalence rate of West Nile virus recorded in North America thus far. Many factors could have influenced this outbreak, such as eco-region, early prolonged hot weather, level of mosquito control programs, urban and rural community differences, and personal protective behaviours. MeSH terms: West Nile virus; seroepidemiologic study; Saskatchewan; knowledge, attitude, behavior

We report on an experiment at the Paul Scherrer Institute, Villigen, Switzerland measuring x rays from muon transfer from deuterium to helium. Both the ground state transfer via the exotic dmu3,4He* molecules and the excited state transfer from mud* were measured. The use of CCD detectors allowed x rays from 1.5 keV to 11 keV to be detected with sufficient energy resolution to separate the transitions to different final states in both deuterium and helium. The x-ray peaks of the dmu3He* and dmu4He* molecules were measured with good statistics. For the D2+3He mixture, the peak has its maximum at E_dmu3He = 6768 +- 12 eV with FWHM Gamma_dmu3He = 863 +- 10 eV. Furthermore the radiative branching ratio was found to be kappa_dmu3He = 0.301 +- 0.061. For the D_2+4He mixture, the maximum of the peak lies at E_dmu4He = 6831 +- 8 eV and the FWHM is Gamma_dmu4He = 856 +- 10 eV. The radiative branching ratio is kappa_dmu4He = 0.636 +- 0.097. The excited state transfer is limited by the probability to reach the deuterium ground state, q_1s. This coefficient was determined for both mixtures: q^3He_1s = 68.9 +- 2.7% and q^4He_1s = 90.1 +- 1.5., Comment: 9 pages, 11 figures

We report a 64-year-old female with predominantly bulbar amyotrophic lateral sclerosis who experienced 'roaring' in her ears. She was diagnosed with patulous Eustachian tube, which is presumed to occur secondary to bulbar weakness. The roaring adversely affected the management of her ALS by impairing her ability to tolerate BiPaP. A review of the relevant literature is reported.

We have observed the deexcitation x-ray spectra of the exotic molecules $(d{\ensuremath{\mu}}^{4}\mathrm{He}{)}^{*}$ and $(d{\ensuremath{\mu}}^{3}\mathrm{He}{)}^{*}$ with good statistics and low background. From the time distributions of these x rays, we have directly determined the muon transfer rates from ground-state muonic deuterium atoms to helium nuclei. The obtained transfer rates in gaseous mixtures at $\ensuremath{\sim}30$ K are ${\ensuremath{\lambda}}_{{d}^{3}\mathrm{He}}=(1.856\ifmmode\pm\else\textpm\fi{}0.077)\ifmmode\times\else\texttimes\fi{}{10}^{8} {\mathrm{s}}^{\ensuremath{-}1}$ to ${}^{3}\mathrm{He},$ and ${\ensuremath{\lambda}}_{{d}^{4}\mathrm{He}}=(10.50\ifmmode\pm\else\textpm\fi{}0.21)\ifmmode\times\else\texttimes\fi{}{10}^{8} {\mathrm{s}}^{\ensuremath{-}1}$ to ${}^{4}\mathrm{He}.$ In liquid mixtures, we measured the muon transfer rates ${\ensuremath{\lambda}}_{{d}^{3}\mathrm{He}}=(2.77\ifmmode\pm\else\textpm\fi{}0.73)\ifmmode\times\else\texttimes\fi{}{10}^{8} {\mathrm{s}}^{\ensuremath{-}1}$ and ${\ensuremath{\lambda}}_{{d}^{4}\mathrm{He}}=(14.2\ifmmode\pm\else\textpm\fi{}1.4)\ifmmode\times\else\texttimes\fi{}{10}^{8} {\mathrm{s}}^{\ensuremath{-}1}.$ These transfer rates have to be multiplied with the target density and the atomic helium concentration to obtain the ``effective transfer rates'' for a specific target composition. The expected isotopic effect between mixtures containing ${}^{3}\mathrm{He}$ and mixtures containing ${}^{4}\mathrm{He},$ as well as with respect to the hydrogen-helium case, is clearly confirmed. A density effect was observed for both isotopic compositions. We investigated the widths and the energies of the intensity maxima of the observed energy spectra of the molecular x rays. From the comparison of the measured energy spectra with calculated ones, we conclude that decay from the rotational state $J=1$ of the muonic molecule dominates over decay from $J=0$ at the investigated experimental conditions.

Compared with conventional modes of patient-initiated mechanical ventilation, respiratory mechanical unloading aims at improving the match between ventilator pressure profiles and the specific derangements in lung mechanics. This may reduce lung barotrauma. The ventilator pressure increases either in proportion to the volume or to the flow of spontaneous breathing (elastic or resistive unloading), thereby selectively decreasing elastic or resistive work of breathing. The clinician sets a gain of increase in pressure per unit of volume or flow. In an attempt to develop criteria for selecting an appropriate gain, we investigated the effects of unloading using increasing gains that either partially compensated or overcompensated lung elastance or resistance. We studied spontaneously breathing, anesthetized, and tracheotomized rabbits. Compared with continuous positive airway pressure, respiratory unloading decreased the electromyographic activity of the diaphragm and increased minute ventilation in normal (n = 5) and surfactant-depleted (n = 6) animals when the gain was partially compensating. Fluctuations in systemic blood pressure associated with breathing decreased. The end-expiratory lung volume remained unchanged. Overcompensation of lung elastic recoil during elastic unloading with an excessive gain caused large tidal volumes associated with a cyclic decrease in blood pressure. Overcompensation of resistance induced oscillations. Complete inhibition of spontaneous breathing occurred with a further increase in gain. We conclude that respiratory unloading with an appropriate gain enhances the effect of diaphragmatic muscle activity on ventilation. A stable breathing pattern ensues whenever a regular spontaneous effort is present. However, excessive gain causes large tidal volumes during elastic unloading or oscillations during resistive unloading.

FIRST PREFACE - 'The most important experiment to be carried out in low energy K-meson physics today is the definitive determination of the energy level shift in the K-p atoms, because of their direct connection with the physics of KN interaction and their complete independence from all other kinds of measurements which bear on this interaction'.